A build-up of heat in a compost heap almost cost Rotorua Lakes High School a classroom. Now the fire service wants people to make sure there is at least 1m between their compost heaps and buildings or fences.
The school's caretaker, Colin Clarke, smelt and saw smoke on Sunday around 9.30pm, and called 111. It was his swift actions that saved the school from losing its horticultural classroom, principal Bruce Walker said.
"It was major," Mr Walker said.
"Thank God the caretaker had alerted [the fire service]. It was close enough to the building, another half an hour and we could have lost that classroom. It's been a big learning curve for us and our community. People don't realise how hot compost gets - we had potatoes roasting in it.
"We're very lucky and we appreciate the fire brigade."
The compost heap was moved yesterday morning and Mr Walker said he had checked his own compost at home to make sure it would not be a fire risk.
One of the classroom walls had boards removed from the outside to check for hot spots but there was no fire damage. The classroom was aired out yesterday and would be back in use tomorrow - there are no classes today due to athletics.
Horticultural students were moved to other classrooms yesterday.
Sunday night's fire was the second incident at the school over the weekend. The fire service were called out to a grass fire in the middle of the athletics track on Saturday afternoon. A patch of about 18m x 17m was burnt. The damage meant today's javelin competition would be moved to another part of the school.
Rotorua fire investigator Stuart Bootten said the compost fire was a timely reminder for people to check their gardens.
"Definitely don't have them up against sheds, they need to be free-standing with a metre gap around them," he said.
"Compost has amazing heat and with this dry weather it heats up tremendously and can ignite from the fine fuels within it, once it starts to smoulder it sets the wooden frame on fire. Compost will still burn in a plastic bin, it will melt the plastic."
He said this was the first compost fire in Rotorua this year but it was not an uncommon situation.
A shed burned down in Tokoroa on Sunday morning under similar circumstances.